We study the evolution of profits, investment and market shares in US industries over the past 40 years. During the 1990's, and at low levels of initial concentration, we find evidence of efficient concentration driven by tougher price competition, intangible investment, and increasing...

We combine a structural model with cross-sectional micro data to identify the causes andconsequences of rising concentration in the US economy. Using asset prices and industrydata, we estimate realized and anticipated shocks that drive entry and concentration. Wevalidate our approach by showing...

We study the evolution of super star firms in the U.S. economy over the past 60 years. Contrary to common wisdom, super stars firms have not become larger, have not become more productive, and the contribution of star firms to aggregate U.S. productivity growth has fallen by more than one third...

We propose a model to identify the causes of rising profits and concentration, and declining entry and investment in the US economy. Our approach combines a rich structural DSGE model with cross-sectional identification from firm and industry data. Using asset prices, our model estimates the...

We study the evolution of profits, investment and market shares in US industries over the past 40 years. During the 1990's, and at low levels of initial concentration, we find evidence of efficient concentration driven by tougher price competition, intangible investment, and increasing...